1. Field of the Invention
The present invention relates to the general art of surgery, and to the particular field of endotracheal tubes.
2. Discussion of the Related Art
Many patients require long-term use of an endotracheal tube. While such devices are very helpful, they have several problems. Some tubes are difficult to keep in place, for example. Some endotracheal tubes include a cuff that is interposed between the endotracheal tube and the patient""s tissue. This cuff is intended to seal a volume of air in a patient""s lungs.
It has been discovered that, while successful and very helpful in many instances, positive pressure ventilation has risks and complications. Constant high pressure in the cuff and long term positive pressure ventilation is directly related to tracheal stenosis. High pressure decreases blood flow and tissue begins dying adjacent to the cuff during such application of high pressure. During an expiratory phase of a breathing cycle, blood flow is restored.
Therefore, there is a need for an endotracheal tube with a cuff that can remain in place for long periods of time without significant chance of tracheal stenosis.
In some cases, slow leaks can occur because a cuff is either not secure enough or tissue adjacent to the cuff has changed over time. A leak path around the cuff of an endotracheal tube is not desirable. This leak is secondary, the primary leak occurring at the pilot balloon.
Therefore, there is a need for an endotracheal tube system which can remain securely in place to reduce the possibility of slow leaks, yet will not create a significant possibility of tracheal stenosis.
Some endotracheal tube systems include extubation and re-intubation procedures in order to overcome the above-discussed problems. However, in some patients, such as patients with upper airway burns, spasmatic airways or patients who may have an antiphalatic reaction, or the like, these procedures are not an option.
Therefore, there is a need for an endotracheal tube system that can remain securely in place for all patients without requiring extubation and re-intubation.
It is a main object of the present invention to provide an endotracheal tube with a cuff that can remain in place for long periods of time without significant chance of tracheal stenosis while promoting/increasing capillary blood flow during the expiratory phase.
It is another object of the present invention to provide an endotracheal tube system which can remain securely in place to reduce the possibility of slow leaks, yet will not create a significant possibility of tracheal stenosis.
It is another object of the present invention to provide an endotracheal tube system that can remain securely in place for all patients without requiring extubation and re-intubation.
These, and other, objects are achieved by a variable endotracheal tube cuff pressure controller comprising a positive pressure breathing unit, an endotracheal tube fluidically connected to the positive pressure breathing unit, a cuff on the endotracheal tube, the cuff being located between the endotracheal tube and a patient trachea and a pressure control system which includes a port in the endotracheal tube, a moisture-impervious cover mounted on the endotracheal tube adjacent to the port in the endotracheal tube to cover the port in the endotracheal tube, a one-way valve fluidically connected to the port in the endotracheal tube to permit flow of fluid out of the endotracheal tube via the port in the endotracheal tube and to prevent flow of fluid into the endotracheal tube via the port in the endotracheal tube, a pressure manometer fluidically connected to the one-way valve, and a pilot balloon fluidically connected to the manometer and to the endotracheal tube.
The pressure controller of the present invention permits the cuff to expand sufficiently to prevent direct flow in the manner desired, but will also divert flow from the endotracheal tube during an expiratory phase of a breathing cycle so the cells in the patient""s trachea can recover. This provides a fluid-tight fit without creating danger of stenosis in the patient""s trachea adjacent to the cuff.
The system embodying the present invention is connected between the patient circuit and the endotracheal/tracheostomy tube. A port is connected to a pilot balloon. During the inspiratory phase of a patient""s breathing cycle, pressure/volume is transferred from the patient circuit to the cuff through the pilot balloon. During the expiratory or relax phase, the cuff will deflate to a pressure not less than 15 cm of water which prevents aspiration.
One form of the system embodying the present invention includes a spring that is connected to a thumb wheel to make the controlled pressure adjustable. This allows for lower or higher pressure during the expiratory phase and will optimize pressure to promote an increase in capillary blood flow. During the inspiratory phase, pressure in the cuff is determined by the patient circuit generated by the breathing machine.